Kadurina T.I. - Head of research center "TAMKOR", Cand of Sci (Chem), scientific officer
The problem of corrosion of metal and other materials remains a constant concern. One of the most effective ways to fight corrosion and conserve metal resourses is its protection with paints and varnishes.
Currently, technically advanced film formers among paint materials are epoxy, polyurethane and epoxy polyurethane (EPU) polymers. It is no coincidence that the scope of their development and application, as shown by the analysis of scientific and patent literature, is constantly growing. The combination of polyurethane and epoxy film formers (their mutual modification) realizes the possibility of purposeful improvement of the properties of both polyurethane and epoxy polymers.
The presence of urethane groups in the polymer matrix improves the elastic-deformation properties of epoxy polymers (the weakest point of these polymers), as well as improves their elasticity, impact resistance and weather resistance. On the other hand, the combination with epoxides gives polyurethanes increased corrosion resistance, improves adhesion, chemical resistance in aggressive environments and increases heat resistance. EPU polymers have excellent dielectric properties.
What is especially important and what distinguishes EPU from other classes of polymers is the effect of paint materials curing temperature on the structure of the formed material. In EPU film formers, temperature is a decisive factor that affects not only the process of film formation, ie drying of the coating, but also the structure of the final product (paint material).
The principle of modification of polyurethanes (PU) with epoxy compounds was the basis for the creation of high-quality anti-corrosion coatings. It is known that the main protection function of paint materials belongs to the film former, its chemical nature and structure, which must provide the coating with high physical and mechanical properties (adhesive strength, impact resistance and elasticity), which allow the coating to withstand various mechanical damage.
For anticorrosive coatings, in addition to physical and mechanical properties, the protective properties of the film former in aggressive environments play an important role. The protective functions of the coating are determined by a set of properties of the polymer matrix, the main of which are the chemical resistance of the polymer, the diffusion characteristics of the polymer film, as well as the adhesive strength of the film former.
In the pilot study, it was found that epoxy modification of polyurethanes increases the protective life of the coating in water by 10-15 times, in alkali solutions – by 7-8 times, in acid solutions - by 2.5-3 times. A particularly positive effect of epoxy modification of polyurethanes is observed in environments of polar solvents, such as acetone and alcohol, in which unmodified polyurethane coatings do not work.
There is a significant improvement of the protective properties of epoxyurethane coatings in the environments of pesticides (ammonium nitrate, chlorophos, copper sulfate, etc.).
Based on the principle of modification of PU with epoxy compounds and established by fundamental studies of the regularity of formation and interaction of the composition-properties of EPP-film former, a series of highly effective domestic epoxy polyurethane materials was developed.
The company "TAMKOR" produces and supplies the following products to the market of Ukraine:
- epoxy polyurethane paint materials
- enamel EPU33KR
- varnish EPU-042L
- aluminum-filled coatings
- antistatic enamels
- polyurethane paint materials
- enamel PU 53-13E
- varnish PU 053-13L
- zinc-filled paint materials
- sealant "Laprocam"
- alkyd-urethane enamels
